package String;

public class Demo03 {
    public static void main(String[] args) {
        /*
         * 字符串对象是不变的！
         */
        String s1="ABC";
        String s2=s1;
        s1+="DEF";
        System.out.println(s1);//ABCDEF
        System.out.println(s2);//ABC
            }
}
